Flat-sided bottle



FIG. 1 is a front side elevational view of the flat-sided bottle showing my new design, the rear side being identical thereto;

FIG. 2 is a right side elevational view thereof, the left side being identical thereto;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a bottom plan view thereof. 

The ornamental design for a flat-sided bottle, as shown and described. 